I am a member of AAA and as well as Towing they have some free Locksmith Service.

In your case what I have seen the Tow Truck Driver do is put something like a Blood Pressure Cuff between the Door (pried open with a Plastic coated Tool) and inflates it prying your door out enough to stick something in and yank the Key out or pull the Locking Knob up.

If you do the Coat Hanger thing and try to pull up the Locking Knob be patient. If you do not have any thing to pry the Door a little wrap a big Screwdriver with masking or Duct Tape so it does not mar things so much.
It also helps if someone else pries the Door open and you have 2 free hands to manipulate the Coat Hanger.

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84 300D, 82 Volvo 244Gl Diesel